Field of the Invention
This invention pertains generally to the field of aircraft display units that present flight plan information to the pilot or flight crew of an aircraft.
Description of the Related Art
An aircraft may be equipped with a flight management system (“FMS”) for storing and providing the pilot with flight information such as, but not limited to, an approved flight plan. There is more than one method from which the flight plan information may be entered into the FMS. In one method, a pilot may manually enter waypoint information, where a sequence of waypoints may define the flight plan. In another method, the flight plan may be automatically uplinked into the FMS by air traffic control (“ATC”) or a flight dispatch center of the owner or operator of the aircraft through the use of a communication datalink.
A flight plan may be modified at any time during the flight. One such method of modifying the flight plan includes the use of controller-pilot data link communications (“CPDLC”) in which ATC may communicate with the flight crew through the datalink system. Those skilled in the art understand that clearances transmitted via datalink communications may be limited to a small set of messages (potentially several hundred messages) in a structured format. The message formats may be controlled by an aviation industry standard(s) which may evolve slowly under a strict version control process. Because message formats may be highly structured, the FMS could be configured with a software program(s) which parses and interprets the messages. Furthermore, the FMS could be configured with a means to provide the pilot (E.G., a multi-function control display unit (“MCDU”)) for accepting and/or rejecting a proposed modification.
Although an ATC-proposed modification may be uplinked to the flight crew, there may be areas or regions of the world where datalink communications are not available. Alternatively, the physical layout of the cockpit and location of the MCDU may cause the pilot to become distracted and lose focus on flying the aircraft and/or lose his or her ability to maintain situational awareness by keeping his or her attention directed straight ahead. While tactical and strategic flight displays (e.g., colloquially referred to as primary flight displays and navigation displays, respectively) are located directly in the pilot's forward field of view, the FMS MCDU on many aircraft may be found in a location adjacent to the pilot's lap. If the ATC proposal is uplinked from which the pilot has no option but to respond, the distraction caused by the pilot shifting his or her attention downward and to the left or right to view and respond may be detrimental to situational awareness. If the pilot wishes to orally communicate his acknowledgement of the modified flight plan, his or her oral acknowledgement will not modify the flight plan stored in the FMS, creating another potential loss of situational awareness; moreover, if the pilot has selected a “VNAV” and/or “LNAV” mode on a mode control panel associated with an auto flight system, an autopilot may not effectuate any changes of the modified flight plan without the modified flight plan being stored in the FMS.